Spark-plug.



E. C. RAUGH.

SPARK PLUG.

` APPLICATION FILED SBPT.11,1912. 1,098,637. Patented June 2, 1914.

Attorneys 7./ "I sa l f///////%//////////////// /V//////////// Y nLiviEit o. mitici-i, or 00EUR IiALENn, IDAHo.

' SPARK-PLUG.

Specification of Letters Patent.

Patented J une 2, 1914.

Application filed September 11, 1912. Serial No. 719,878.

To all 'whom it may concern.'

Be it known that l, ELMER C. Ration, a 'citizen of .the United States, residing at Coeur dAlene, in the county of Kootenai and State of Idaho, have invented a new and useful Spark-Plug, of which the following is a specilication.

The present invention relates to improvements in spark plugs, the primary object of the invention being the provision of a novel construction of plug, in which the concentric terminal thereof is composed of a removable carbon pencil, the same being disposed to' coact with a surrounding sparking terminal member, thus providing the greatest possible sparking surface, and an exceedingly rich s ark.

PWith the foregoing and other objects in view which will appear as the description proceeds, the invention resides in the combination and arrangement of parts and in the details of construction hereinafter described r and claimed, it being understood that changes in the precise embodiment of the invention herein disclosed can be made within the scope of what is claimed withoutdeparting from the spirit oit' the invention.

In the drawings- Figure 1 is a verticalcentral sectional view through a spark plug made according to and embodying the pres-.

ent invention. Fig. 2 is a section taken on line 2-2 of Fig. 1. Fig. 3 is a view similar to Fig. 1 of a modified form'of spark plug.

Referring to the drawings, and more particularly to Figs. 1 and 2, the numeral 1 designates the metallic plug body the upper end of which is in the form of a head and the lower end 2 of which is reduced eX- teriorly screw threaded 'for engaging the plug socket of an internal combustion engine. The body is provided with a longitudinal bore or channel 6 therethrough, the lower end of which is counter bored as at 3, and threaded as at 3 Fitting within the bore 6 of the member 1 is an insulating bushing or tube 7, the samel being provided with the annular collar 8 which seats within the contracted end 5 of the counterbore 3 and which is flush with the annular shoulder d formed by the port-ion 5. A metallic sleeve 9 is threaded into the counterbore 3 and its upper end engages with the collar 5 and shoulder 4 to lock the insulator member 7 in place, as clearly illustrated. The lower end of the metal member or sleeve 9 is provided with an annular inturned ange or lip forming an annular MiA a longitudinal bore l1 in which is fitted the l metallic rod 12, whose upper end is threaded for the reception of the binding screw 14 and whose lower end 15 is disposed within the enlarged portion or counterbore 16 formed in the lower end of the insulator Amember 7.

The upper threaded end -`oft the rod 12 is threaded Within the upper end of the bore 11, to hold the rod 12 against sliding longitudinally, and to permit the rod 12 to be adjusted longitudinally by rotating it. The sparking terminal 17 has its upper end fitted snugly within the counter-bore 16, and threadedly receives the lower end of the rod 12. This sparking terminal 17 is in reality a carbon pencil, although it is to be understood that any material may beemployed that will produce the desired result, the lower end 18 of the terminal 17 being disposed in co-active sparking relation to the sparking terminal 10 of themember 9.

The carbon pencil or terminal 17 is of uniform diameter throughout its length and has one end portion received snugly by the counterbor'e of the bushing, while itsfree end is passed through the opening formed by the lip 10. f

'ln the form oi spark plug shown in Fig. 3, .the member 19 which corresponds to the member 1 of the spark plug shown in Figs. 1 and 2, is exteriorly threaded and reduced as at 20 for engagement with the plug receiving aperture of any engine, and is provided with the sparking terminal 2l at the lower end thereof. A chamber 22 which corresponds to the chamber of the sleeve 9 of the other form, is provided in the lower end of the member 19, and this member 19 is provided with the concentric bore 23 providing the annular shoulder 24 and the threaded portion 25 open at the upper end of the body 19.

Removably insertible within theinember 19 from the upper end thereof and instead of .from the lower end as shown in Fig. 1,

19 and surrounds the upper end of the in-4 sulator 26.

Disposed concentrically of and through the insulator .member 26 is the terminal rod 30, which has mounted upon its upper end the binding nut 31, while its lower threaded i end 32 removably receives the upper end of the concentric terminal 33, said terminal 33 corresponding with the terminal 17 and disposed to have its lower end in sparking relation to the terminal 21.

From the foregoing description, it is evident that with the construction herein set forth, that the'insulator member bodily carries the removable sparking terminals A17-33, and that by such arrangement the sparking terminal may be removed in case of burn-out or breakage and readily replaced; and also that by' reason of' the threaded portion at 15.-32, the respective terminals may be readily adjusted so as to be placed in the most eicient relation to the sparking terminals 10-21.

What is claimed is:

l1. A -spark plug comprising a metallic plug body having a longitudinal bore provided with a counterbore at its lower end, an insulating bushing fitting within the said bore and having its lower end disposed within the said counterbore, the bushing having a longitudinal bore provided with a coun-l terbore at its lower end, a metallic rod fitting within the bore of the bushing, the lower end of the rod being disposed within the counterbore of the bushing, and the upper end of the rod being threaded within the upper end of the bore of the bushing and pro]ecting from the upper end of the bushing, a binding nut engaged on the upper end ofthe said rod, a sparking terminal comprising a carbon pencil of uniform di'- ameter throughout its length having its upper end fitting within the said coimterbore of the said bushing and threadedly receiving the lower end of the said rod, and an annular sparking terminal carried by the lower end of the plug body and surrounding the lower end of the said sparking terminal.

2. In'a spark plug, a metallic plug body having a longitudinal bore provided with acounterboreat its lower end, an insulatin bushing 'ttmg through the said bore an yhaving its lower end disposed within` the said counterbore, the bushing having a longitudinal bore and a counterbore at its lower end, and having a collar fitting within the upper end of the counterbore of the plug body, a metallic sleeve of uniform diameter throughout its length threaded into the countei-bore of the plug body and engaging the said collar, the lower end of the sleeve having an annular inturned lip, the basal portion of the lip being relatively thick and the free edge being sharpened and forming an opening co-axal with and larger than the counterbore of the bushing, a carbon pencil of uniform diameter throughout its length having one end portion received snugly by the counterbore of the bushing and having its other end passed through said opening formed by the lip, a metallic rod passed through the bore of the bushing and having its lower end threaded into the first mentioned end of the carbon pencil, and a binding nut threaded on the upper end of said rod to seat against the upper end of the bushing. y

3. In a spark plug, a metallic plug body having a longitudinal bore provided with a counter bore at its lower end, an insulating bushing fitting within the said bore and having its-lower end disposed within the said counter bore, the bushing having a longitudinal bore provided with a counter bore at its lower end, and having a collar tting within the upper end of the counter bore of the plug body, a metallic rod fitting withinthe .bore of the bushing, the lower end of the rod being disposed within the counter bore of the bushing, and the upper end of the -rod being threaded within the upperV end of the bore of the bushing. and proJecting from the upper end of the bushing, a binding-mut engaged on the upper end of the said rod, a metallic sleeve of uniform diameter throughout its length threaded into the counter bore of the plug body and engaging the said collar, the lower end of the sleeve having an annular inturned lip forming an opening coaxial with and larger than the counter bore of the bushing, and a carbon pencil of uniform diameter throughout its length having one end portion received snugly-'by the counter bore of the bushing and threadedly receiving the lower end of the said rod, the carbon pencil projecting through thev saidopening formed by the lip.

In testimony that I claimthe foregoing as my own, I have hereto affixed my signature in the presence of two witnesses.

ELMER C. BAUCH.

Witnesses:

EARL P. BROWN, l A. L. RAUCH. 

